This is the project engineering file, which contains all the files you have generated in this project, including operations like merging, Boolean operations, and so on. If you don’t want it, you can click the “R” in the upper right corner. However, you must make sure to save the file first. Otherwise, once you click “R”, the file cannot be restored or retrieved.
Thanks for the reply. Someone else told me about the macro: delete unselected tools.